Although Diesel injection was previously a domain of purely mechanical construction, electronics technology has rapidly gained ground in this field. It is known, for instance, to control the regulating rod of an injection rod by means of an electromagnet system, which in turn receives its input pulses from an electronic regulating device. Because of the electronics, the possibilities for manipulation are virtually unlimited, so that in fact all the parameters associated with an internal combustion engine can be taken into consideration in the course of control.
One important operating characteristic in the regulation of an internal combustion engine with externally-supplied ignition is the injected fuel quantity. It is known either to determine the injection quantity directly, by means of a flow-through quantity meter, or instead to evaluate the position signal of the regulating rod as a quantity signal. While in the first measurement method, the very small injection quantities per unit of the time cause difficulties, the second method has the deficiency that the metered fuel quantity is detected only by indirect means, and it is thus not possible to furnish measurement results which are independent of the effects of aging.